Stun grenades, or “flash-bang” devices are used by military and law enforcement as non-lethal devices intended to distract or stun dangerous suspects or adversaries. Such devices are deployed to minimize hostile responses, and to generate compliance.
A typical existing device employs a “single bang” provided by a quantity of flash-charge material (such as a mixture of aluminum powder and potassium perchlorate) that is detonated after a brief delay. A fuse is activated by release of a handle as in a typical grenade, and the fuse ignites a column of delay material (such as black powder or Zirconium Nickel). The column provides a delay (typically ½ second) until the flame front in the delay material reaches an aperture that communicates with the flash-charge material, igniting it to provide a bright flash and loud report.
One such device is shown in U.S. Pat. No. 5,654,523 to Brunn, titled “Stun Grenade.” This “single-bang” device has an advantageous configuration. Like many others, it is a cylindrical body sized to readily be gripped by an adult hand, so that the device is secure in the user's fist, with the ends of the cylinder protruding beyond each end of the user's fist. The disclosed device has the advantage that all the vent holes for releasing the energy of the flash charge material come out the ends of the grenade body. While a device normally discharges only after a delay following release by the user, there is a remote possibility that the grenade may discharge while still in the user's hand, such as if the user is distracted, or the device snags on the user's glove. The disclosed device minimizes the risk of serious injury in such an event by discharging the combustion gases out the ends of the device, with no apertures in the cylindrical sidewall of the device.
Other devices have sought to provide added tactical effectiveness by employing a device with multiple reports in a single grenade. Such a device is the 9-Bang grenade produced by Nico-Pyrotechnik of Düsseldorf, Germany. This is a cylindrical body with a similar form to the Brunn device. It is a solid steel or aluminum body with a central axial delay column. The cylindrical sidewall of the body is bored with nine chambers, each providing a cup that opens radially outward, giving the body the approximate appearance of a cylindrical piece of “Swiss cheese.” Each cup is filled with flash charge material and has a different position along the length of the body. A small hole is bored from the floor of each cup to the central delay column, with each hole at a different position along the length of the column. This provides for the charges in each cup discharging in sequence as the flame proceeds down the delay column. Accordingly, a useful sequence of many bangs (and flashes) is generated upon discharge of the device, simulating repeated gunfire instead of a single loud report.
The Nico device suffers the disadvantage of having the flash charge materials projecting their discharge energy exactly where a user's hand grips the device, risking serious injury in the event of a discharge while the device is still being held.
Accordingly, there is a need for a multiple-report stun grenade device that provides safe function even in the event of unexpected discharge while in a user's hand.
The present invention overcomes the limitations of the prior art by providing a stun grenade device with an elongated cylindrical body having a cylindrical sidewall and opposed top and bottom end faces. The body includes a delay chamber containing a delay material, and has a number of flash charge chambers each containing a quantity of flash charge material. The body defines a number of ignition passages, each communicating from a respective flash charge chamber to the delay chamber. Each flash charge chamber has at least one exhaust aperture penetrating the top or bottom end face. Each flash charge chamber may be formed in an elongated tubular sleeve inset in a frame of a different material.